T. Csoti et al., Aluminum enhances the voltage activated sodium currents in the neurons of the pond snail Lymnaea stagnalis L., ACT BIOL HU, 50(1-3), 1999, pp. 35-42
1. The effects of aluminum on voltage activated sodium currents (VASCs) wer
e investigated by using the conventional two-electrode voltage clamp techni
que in Lymnaea stagnalis L. neurons. The peak amplitude, kinetics, and volt
age-dependence of activation and inactivation of the sodium currents were s
tudied in the presence of 5-500 mu M AlCl3, at pH = 7.7.
2. There was a significant concentration-dependent increase in the peak amp
litude of sodium currents after Al treatment, ED50 = 67 mu M. The threshold
concentration of the enhancement was 50 mu M. The maximal peak increase of
143% was caused by a 500 mu M aluminum. The action of aluminum on VASCs de
veloped slowly, and it is not recovered by washing within 20 min.
3. There was little alteration of the voltage-dependence of the current. It
was not a significant effect on the activation- and inactivation time cons
tants of I-Na, but the steady-state inactivation curve shifted to negative
direction on the voltage axis in the presence of Al.
4. The leak currents were not influenced by aluminum up to the highest conc
entration applied.